Table 2.
Evolution of malariometric indices across 6 consecutive cross sectional surveys
| Cross sectional surveys: Date |
S1 04/2004 |
S2 12/2004 |
S3 04/2005 |
S4 12/2005 |
S5 04/2006 |
S6 12/2006 |
| Participants, N | 1,518 | 2,068 | 2,081 | 2,089 | 2,102 | 2,018 |
|
Malaria prevalence: n (%) [95%CI] By species: |
178 (11.7) [6.8; 19.5] |
281 (13.6) [8.8 ; 20.5] |
126 (6.1) [3.5; 10.4] |
173 (8.3) [4.6; 14.4] |
116 (5.5) [2.6; 11.5] |
80 (4.0) [2.3; 6.8] |
| - P. falciparum | 85 (5.6) | 148 (7.1) | 57 (2.7) | 103 (4.9) | 61(2.9) | 49(2.4) |
| - P. vivax | 77 (5.1) | 93 (4.5) | 52 (2.5) | 55 (2.6) | 43 (2.0) | 27 (1.3) |
| - P. malariae | 3 (0.2) | 2 (0.1) | 2 (0.1) | 7 (0.3) | 0 (0.0) | 0 (0.0) |
| - Mixed infections | 13 (0.9) | 38 (1.8) | 15 (0.7) | 8 (0.4) | 12 (0.6) | 4 (0.2) |
| Asymptomatic infections* | 153 (86.0) [66.4; 95.0] |
230 (81.9) [67.7; 90.7] |
97 (77.0) [40.6; 92.4] |
139 (80.3) [70.2; 87.7] |
99 (85.3) [68.0; 94.1] |
68 (85.0) [75.6; 91.21] |
|
Parasite density/μl (GM)° [95%CI] |
||||||
| P. falciparum | 187.9 [129.0–273.7] | 169.0 [124.1–230.1] | 172.6 [112.7–264.4] | 225.0 [149.1–339.7] | 245.0 [154.0–389.8] | 370.5 [205.8–667.0] |
| P. vivax | 76.3 [59.7–97.5] | 79.5 [59.8–105.9] | 68.6 [47.9–98.2] | 81.2 [52.1–126.5] | 82.1 [52.7–127.8] | 145.1 [83.5–252.4] |
| P. malariae | 140.7 [54.1–365.5] | 81.1 [12.7–515.8] | 148.1) [39.4–557.1] | 93.5 [87.8–99.7] | - | - |
|
Gametocyte prevalence, n (%) [95%CI] |
65 (4.3) [2.4; 7.4] |
166 (8.0) [3.0; 19.8] |
33 (1.6) [0.7 ; 3.4] |
55 (2.6) [1.5 ; 4.6] |
44 (2.1) [0.9 ; 4.7] |
21 (1.0) [0.4 ; 2.5] |
| Malaria prevalence by age group | ||||||
| - <9 years | NA | 101 (17.5) [11.3; 26.0] |
54 (10.4) [5.3; 19.6] |
59 (11.5) [6.8; 18.8] |
42 (9.1) [4.2; 18.7] |
28 (6.3) [3.6; 10.8] |
| - 10–19 years | 70 (13.6) [7.3; 23.8] |
78 (15.7) [9.3; 25.3] |
35 (6.6) [3.3; 12.6] |
41 (7.9) [3.5; 16.6] |
37 (6.9) [3.1; 14.9] |
28 (5.4) [2.9; 9.8] |
| - 20–29 years | 49 (11.8) [6.3; 20.2] |
42 (10.2) [5.9; 17.1] |
10 (2.4) [0.8; 7.0] |
27 (6.1) [3.5; 10.5] |
15 (3.3) [1.2; 9.1] |
9 (2.2) [0.9 ; 4.9] |
| - 30–39 years | 30 (11.0) [7.1; 16.7] |
19 (7.5) [3.6; 15.0] |
15 (5.3) [2.7; 10.0] |
23 (7.7) [3.5; 16.3] |
7 (2.5) [0.6; 8.9] |
5 (1.8) [0.7 ; 4.9] |
| - 40–49 years | 20 (11.1) [5.8; 20.2] |
27 (13.8) [7.5; 24.2] |
8 (3.9) [1.0; 14.1] |
17 (9.6) [4.4; 19.8] |
10 (4.4) [1.6; 11.9] |
7 (3.2) [1.3; 7.8] |
| - ≥ 50 years | 9 (6.8) [2.8; 15.6] |
14 (10.5) [5.2; 20.1] |
4 (3.1) [1.3; 7.5] |
6 (4.3) [1.8; 10.2] |
5 (3.5) [1.2; 9.8] |
3 (2.0) [0.6; 6.7] |
| Spleen rate | 29 (1.9) [6.8; 19.3] |
7 (0.3) [8.8; 20.5] |
4 (0.2) [3.5; 10.4] |
5 (0.2) [4.6; 14.4] |
4 (0.2) [2] |
4 (0.2) [2.3; 6.8] |
* % asymptomatic infections/all infections; ° GM: geometric mean